Gear-cutting machine.



F. J. SPENCERKzLJ. SPEIRS. GEAR CUTTING MAGHINE.

APPLICATION FILED DEC. 31, 1901.

946,1 6 1 I Patented Jan. 11, 1910.

F. J. SPENCER 8: J. SPEIRS. GEAR CUTTING MACHINE. APPLICATION-FILED DEG.31.1907.

Patented Jan. 11,1910.

8 SHEETS-SHEET 2.

11. J. SPENCER & J. SPBIRS. GEAR CUTTING MACHINE. APPLICATION FILED DEC. 31. 190'].

. P1161181 Jan. 11,1910.

3 SHEETS-SHEET 3.

WITNESSES.- INVENTORS' By v %%M%W I Alfomcy 2a of the gear to be cut.

UNITE sm-asses ATENT orsion.

FRANK J. Seances. AND .rAM s seams, or nannies-serum), ENGLAND.

GEAR-CUTTING MACHINE.

m a specification.

This invention relates to gear cutting ma- .chines'and particularly to a new or improved universal gear cutting machine for cutting toothed gears by means of two or more sets 5 of reciprocating cutters, each cutter in each set having sides and faces m'contours of the shape of the outline or contour of the tooth of a rack or gear, the exact form be.ng or comprising the base of the system The object of our invention is to provide in an improved construction of machine, by which the use of templets or the cutting of special cutters for each gear is dispensed with, one set of cutters for each pitch notwithstanding the number of teeth-to be cut in the wheel and means to obviate the spacing of the blank after each cut, the arrangement and mode of operation of the ma- S5) chine avoiding the transmission of strains -'0 the machine, and accelerating the cutting of toothed gears.

According to our invention, we emplpy preferably wo tool holding or cutter carriages each carrying a series of cutterswhose form is the ha of a rack or gear tooth, the said carriages e ng located at opposite sides of the machine sothat the cutters may oper-' ate on two separate portions of the wheel 40 ,blank at one time, or more than two carriages may bg employed if required.

The cutting t'oo s are of special construction to cut" both on the forward and backward cutting strokes, and they are each mounted on studs secured to housings which are pivotally mounted on respective car- .riages in order that the cutters may have a slight angular movement to allow them to assume proper angles for clearing and u cutting on both strokes of the carriages 'or blank. The gangs or series of cutters are fed past the blankat the'requisite speed by a feed motion, rigidly controlled by mech fanism whichfcontrols the Worm shaft from 5? which the blank is rotated, such worm shaft ,;being controlled through a differential mo- Specification of Letters Patent.

Patented Jan. 11, 1910.

Application filed December 31, 1907. Serial No. 408,861.

tion and change speed wheels and the whole of the sald mechanism controlled through reversmg bevels on a shaft driven by feed mechanism. The differential gear on the 53 worm shaft is provided to give extra rotation to the wheel blank in order that the parts which are uncut when the cutters have passed beyond the blank in one direction,

may be brought to such a position as to be 5.5

operated upon by the cutters whenthe carriages make the return stroke, the said differential gear being controlled for this purpose from one of the cutter carriages.

If necessary, sufficient cutters are secured in the carriages to cut the wheel in one operation.

The reciprocating cutters are arranged so that one half move in an opposite direction to the other half, whereby the strains are not 7.5

communicated to the machine but kept con tained within the wheel blank which is being cut. hen the carriages are thus moved in opposite directions with the wheel blank between them, they form a couple congo tained in the blank itself which would continue to rotate and be cut at the proper pitch if the mandrel and feeding mechanism were entirely removed for the time being fronrits center.

The invention will be hereinafter fully described and more particularly pointed out in the appended claims. reference being bad to he accompanying drawings, in which l 'igure l is a plan view of a gear cutting machine embodying our improvements; Fig. 2 is a sectional elevation taken on line A. B. of Fig. 1; Figs. 3, 4 and 5 are respectively, front. elevation, sectional pl an view, and transverse section of the holder constructed according to our inven-- tion; Figs. (5 and 7 are respectively, transverse section and plan view of the tools and tool holder as constructed and arranged for cutting internal toothed wheels; Fig. 8 is a detail plan view of the carriage m. Fig. 9 a detail end view of the nut 12: and Fig. 10 is a plan view of the same. Fig. 11 is a detail plan view of the reversible clutch mechanism connected to the wheels c referring to the drawings, and firstly to Figs. l'to 5, letter n represents the framing of the machine and Z the main driving shaft of the machine to which motion is conveyed from any suitable line shaft by belt, and cone tools and tool d, (2 formed in the framework of the machine. The face plate is provided with a worm wheel (1 which mesheswith a worm 0 fast on a shaft 6" adapted to be driven through a differential gear 6' chan e speed wheels 6 and reversm bevel w eels e, from a constantly rotating shaft f. The said. shaft f obtains its motion through worm wheel and worm g (Iig.- 2) from a shaft h having a cone pulley h thereon which driven by belt from a cone pulley '1' fast on a longitudinal screwthreaded shaft or worm shaft j driven by b'evel gears I: from the main driving shaft b. V A screw threaded shaft or worm shaft j similar to the worm shaft 1' is provided at the opposite side of the machine and is driven from the main shaft 1) by bevel wheels la. The worm. shafts j and j mesh with worm wheels l, m, mounted on carriages Z, m, supported by and adapted to slide endwise on guides at, n, the said carriages being made to receive tool holders l, m, in which are. secured the tools or; cutters p, p which extend "inwardly toward the center of the machine. 'lhetoolholders Z and m are provided with dovetailed grooves 3 which are slidable. vertically on dovetailed projections 4 on thecarriages l and m respectively, as shown in Fig. 8, and the said tool-holders are provided with any approved means for sliding them vertically to any desired position and for securing them in that position. This vertical adjustment is commonly used for toolholders. and it does not form an essential part of the present invention. The car riages Z and m are slidable on or in the guides 11 and a. the said parts being constructed in anyapprovcd manner whichavlll permit the carriages to slide freely lengthwise of the guides.

lhe principal feature of our invention t he two or more sets of cutters being adaptedto operate at the same time on different portions of the wheel blank to cut a series of.

teeth on two or more sections of the blank in one traverse of each carriage in. one di-" rection, and another Sllt-ESOf teet h n two or more uncut sections ofth'ehln k: onthe return traverse of the t 'f'e cutter or tooli holders being recip a g iy'ertically."

oneach travc :se and the cutters-normed to cut on each stroke, Each gang or :set of cutters is mounted on studs 1)? in a. housing 79 which is itself'pivotedon a stud or spin dle 12 secured to the respectivetool holder, the housing p being movable about said stud p within limits fixed by set screws g (Fig. 2), in order that the cutters may have a slight. movement in a vertical plane to allonthem to assume proper angles for clearing and cutting on both strokes of the carriage. The wheel blank, indicated by dotted line at '1", is secured to the face plate (1 in any Well known manner, being supported thereon in a horizontal plane coinciding approximately with the position of the cutters when about mid-way of their, vertical movement, somewhat as illustrated.

The carriages are fed. to and past the blank 1- at the requisite speed by the screwthreaded shafts or worm shafts s, 8 working through nuts 12 on the carriages and driven by reversing bevels s, s from vertical shafts driven by bevel gears from the shaft f, one carriage, as Z, moving to the right. (Fig. 1), and the other carriage, as m, moving to the left,'the cutters carried by eachcarriage en gaging with the wheelflfblan'k at the same time and cutting spaces therein to form the teeth as the carriagestravel-past, the number of spacesc'ut in each side of the wheel blank being equivalent to the number ofcutters employed ineach gang or set. During this longitudinal traversing movement of the carriages lym the tool holders Pym are caused to have a rising andfalling reciproeating movement by means of disks it (one onlyibeing shown at Fig. 1) secured on the axes of the worm wheels'l, m driven from the worm shafts j, j, and having studs or pins 13 projectingeccentrically therefrom which enter horizontal. slots 14 in the tool holders, the pin and slot connection giving an up and down movement to the respectiv: tool holders, whereby the eutters or tools are carried up and down to an extent exceeding the depth of the wheel blank, and they out both on their downward and upward strokes, the wheel blank being fed forward'by the worm e and worm wheel d at a rate relative tothe traverse of the carriages l, m and moving in the same direct-i on at the points of contact, the cutters thus cutting their respective-spacesin the wheel blank and completing same by the time the cutters move out of mesh with the blank on the carriages approaching the. extremity of their movement in one direction. When the cutters; have passed clearof the wheel blank. afstop Z? on the carriage Z comes into engagement with a projection or adjustable collar a on'a'rod tit-which is forced 'endwisc in the-same direction and through a lever w'-' connected therewith .relea'ses and-allows to be set in actlon'a dividmgmechanism of any -u'sualwell known type (not shown), which throughz-spurtj g sv ul 'fand bevel. gears u, and the differential gear e'-' gives a quicker motion'to the shaft e'" and through worm e and worm w eel d the wheel blank is revolved forwal d througha space relatively equal-to the space taken up by a set or gang of cutters so as to present uncut sections im. mediately following the cut sections in positions for being operated on by the gangs of cutters on their return stroke. The members of the clutches a, s, e enter or engage simultaneously, the dogs or teeth thereof being arranged so that they cannot free the motion in one'direction until they have entered that in the reverse direction (the slip of the belt allowing for this h'whereby the relative positions of the cuttei an d' wheel blank are maintained, and it will not affect the accuracy of thewheel being out no matter if the dividing takes place before, after, or during the reversal of the mechanism, for

as the dividing is taking place through the differential c, it is independent of any other motion. The wheels a haveclutch members and 23 on them, and a double. clutch member is connected operatively with the shaft and engages with the clutch members 20 and 23 by means of its parts 21 and 22 as shown in Fig. 11, when slid on the shaft by means of'the arm 43. The wheel 8 are provided with clutch members of. similar construction to the clutch members of the wheels 6*. A second collar u on the rod u is engaged by the stop Z" on the carriage in its return stroke to set in motion the dividing mechanism to give a forward movement to the wheel blank at the end of such stroke to present other uncut sections of the blank for the next traverse of the cutter carriages.

The motion of worm shafts 8, s ts reversed at the end of each stroke by a projection '01 on the carriage Z engaging a collar '0' or v on a rod '0 which through levers v and clutch boxes, reverses the motion of the bevels e and s, s and consequently of the parts driven thereby.

By the movement of the carriages carrying the cutters in opposite directions with the wheel blank between them, a couple is formed contained in the blank itself, which would continue to rotate and. be out at the pro er pitch if the mandrel and feeding mec anism were entirely removed for the time being from itscenter.

A cross feed comprising screws or worms 11$, w? is provided for bringing the tool carriages nearer to the center of the machine, the guides 13, n being adapted to slide along the rails a. By actuating the screwsor worms to", 'w the requisite amount during cutting, wheels with pitch lines other than circular may be cut, as in elliptic or like wheels. A levei w-pivoted at 'w and connected to the bracket carryin the worm e and shaft 6, isemployed in or er that when 4 ever necessary for any purpose, the said wbrm may be moved out of engagement with the worm wheeld the disconnection of the worm e from the Worm wheel at permitting the wheel blank when out to be driven by its own worm or wheel and thus ground in its the machine. I t

For cutting the teeth of internal wheels a. gang of cutters p arranged on a circular arc is mounted on a stud p as shown in Figs 5,6 and 7. The housing p is arranged-tqoverban the wheel rim 7' and is pivoted on the sha t 12 When this device is used it is not position without removal from I connected to the traversing mechanism, but

it is 'reciprocated in a. vertical plane only..

What we claim is: i

1. In a gear-cutting machine, the combina-;

blank; of a guide-arranged to one side of the said face-plate'and in a plane parallel to its face, a carriage slidable longitudinally of the saidguide, reversing mechanisms for changing the direction of the revolution of the faceplate and the direction of the travel of the carriage, tappet-mechanism operated by the carriage and actuating the said reversing mechanisms simultaneously, a toolhold'er slidable in the said carriage crosswise of the said guide, means for revolving the face-plate and for sliding the carriage so that they move in timed relation, and driving devices for reciprocating thesaid toolholder.

2.'In' a gear-cutting machine, the combination, with a supportin frame, and a face-plate for carrying the w eel-blank journaled in the said frame; of two parallel uides arranged one on each side of the said ace'plate, carriages slidable longitudinally on the said guides, driving devices operating to slide the said'carriages simultaneously in opposite directions, reversing mechanisms for changing the direci u of the revolution of the said face-plate and the direction of the travel of the said carriage: tappetmechanism operated by one of the said car- 'riages and actuating the said reversing mechanisms simultaneously, tool-holders slidable in the said carriages crosswise of the said guides, and driving devices for reciprocating the said tool-holders.

In testimony whereof we aflix our signatures in the presenoe'of two witnesses.

F RANK J. SPENCER. JAMES SPEIRS.

. THOMAS H. Baum 

